/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
/*
 * Copyright 2005 Sun Microsystems, Inc. All rights reserved.
 */
package org.apache.jcp.xml.dsig.internal.dom;

import javax.xml.crypto.MarshalException;
import javax.xml.crypto.dom.DOMCryptoContext;
import javax.xml.crypto.dsig.XMLSignature;
import javax.xml.crypto.dsig.keyinfo.KeyName;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;

/**
 * DOM-based implementation of KeyName.
 *
 */
public final class DOMKeyName extends DOMStructure implements KeyName {

    private final String name;

    /**
     * Creates a <code>DOMKeyName</code>.
     *
     * @param name the name of the key identifier
     * @throws NullPointerException if <code>name</code> is null
     */
    public DOMKeyName(String name) {
        if (name == null) {
            throw new NullPointerException("name cannot be null");
        }
        this.name = name;
    }

    /**
     * Creates a <code>DOMKeyName</code> from a KeyName element.
     *
     * @param knElem a KeyName element
     */
    public DOMKeyName(Element knElem) {
        name = knElem.getFirstChild().getNodeValue();
    }

    @Override
    public String getName() {
        return name;
    }

    @Override
    public void marshal(Node parent, String dsPrefix, DOMCryptoContext context)
        throws MarshalException
    {
        Document ownerDoc = DOMUtils.getOwnerDocument(parent);
        // prepend namespace prefix, if necessary
        Element knElem = DOMUtils.createElement(ownerDoc, "KeyName",
                                                XMLSignature.XMLNS, dsPrefix);
        knElem.appendChild(ownerDoc.createTextNode(name));
        parent.appendChild(knElem);
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (!(obj instanceof KeyName)) {
            return false;
        }
        KeyName okn = (KeyName)obj;
        return name.equals(okn.getName());
    }

    @Override
    public int hashCode() {
        int result = 17;
        result = 31 * result + name.hashCode();

        return result;
    }
}
